PCI: handle Virtual Function ATS enabling

The SR-IOV spec requires that the Smallest Translation Unit and
the Invalidate Queue Depth fields in the Virtual Function ATS
capability are hardwired to 0. If a function is a Virtual Function,
then and set its Physical Function's STU before enabling the ATS.

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Yu Zhao 2009-05-18 13:51:33 +08:00 committed by David Woodhouse
parent 302b4215da
commit e277d2fc79
2 changed files with 55 additions and 15 deletions

View File

@ -491,10 +491,10 @@ found:
if (pdev)
iov->dev = pci_dev_get(pdev);
else {
else
iov->dev = dev;
mutex_init(&iov->lock);
}
mutex_init(&iov->lock);
dev->sriov = iov;
dev->is_physfn = 1;
@ -514,11 +514,11 @@ static void sriov_release(struct pci_dev *dev)
{
BUG_ON(dev->sriov->nr_virtfn);
if (dev == dev->sriov->dev)
mutex_destroy(&dev->sriov->lock);
else
if (dev != dev->sriov->dev)
pci_dev_put(dev->sriov->dev);
mutex_destroy(&dev->sriov->lock);
kfree(dev->sriov);
dev->sriov = NULL;
}
@ -723,19 +723,40 @@ int pci_enable_ats(struct pci_dev *dev, int ps)
int rc;
u16 ctrl;
BUG_ON(dev->ats);
BUG_ON(dev->ats && dev->ats->is_enabled);
if (ps < PCI_ATS_MIN_STU)
return -EINVAL;
rc = ats_alloc_one(dev, ps);
if (rc)
return rc;
if (dev->is_physfn || dev->is_virtfn) {
struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn;
mutex_lock(&pdev->sriov->lock);
if (pdev->ats)
rc = pdev->ats->stu == ps ? 0 : -EINVAL;
else
rc = ats_alloc_one(pdev, ps);
if (!rc)
pdev->ats->ref_cnt++;
mutex_unlock(&pdev->sriov->lock);
if (rc)
return rc;
}
if (!dev->is_physfn) {
rc = ats_alloc_one(dev, ps);
if (rc)
return rc;
}
ctrl = PCI_ATS_CTRL_ENABLE;
ctrl |= PCI_ATS_CTRL_STU(ps - PCI_ATS_MIN_STU);
if (!dev->is_virtfn)
ctrl |= PCI_ATS_CTRL_STU(ps - PCI_ATS_MIN_STU);
pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
dev->ats->is_enabled = 1;
return 0;
}
@ -747,13 +768,26 @@ void pci_disable_ats(struct pci_dev *dev)
{
u16 ctrl;
BUG_ON(!dev->ats);
BUG_ON(!dev->ats || !dev->ats->is_enabled);
pci_read_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, &ctrl);
ctrl &= ~PCI_ATS_CTRL_ENABLE;
pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
ats_free_one(dev);
dev->ats->is_enabled = 0;
if (dev->is_physfn || dev->is_virtfn) {
struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn;
mutex_lock(&pdev->sriov->lock);
pdev->ats->ref_cnt--;
if (!pdev->ats->ref_cnt)
ats_free_one(pdev);
mutex_unlock(&pdev->sriov->lock);
}
if (!dev->is_physfn)
ats_free_one(dev);
}
/**
@ -765,13 +799,17 @@ void pci_disable_ats(struct pci_dev *dev)
* The ATS spec uses 0 in the Invalidate Queue Depth field to
* indicate that the function can accept 32 Invalidate Request.
* But here we use the `real' values (i.e. 1~32) for the Queue
* Depth.
* Depth; and 0 indicates the function shares the Queue with
* other functions (doesn't exclusively own a Queue).
*/
int pci_ats_queue_depth(struct pci_dev *dev)
{
int pos;
u16 cap;
if (dev->is_virtfn)
return 0;
if (dev->ats)
return dev->ats->qdep;

View File

@ -234,6 +234,8 @@ struct pci_ats {
int pos; /* capability position */
int stu; /* Smallest Translation Unit */
int qdep; /* Invalidate Queue Depth */
int ref_cnt; /* Physical Function reference count */
int is_enabled:1; /* Enable bit is set */
};
#ifdef CONFIG_PCI_IOV
@ -255,7 +257,7 @@ extern int pci_ats_queue_depth(struct pci_dev *dev);
*/
static inline int pci_ats_enabled(struct pci_dev *dev)
{
return !!dev->ats;
return dev->ats && dev->ats->is_enabled;
}
#else
static inline int pci_iov_init(struct pci_dev *dev)